Ordering by number: this is H3437857 (also carried as 3310190012), the Chicago Pneumatic spring. It supplies the return force for its assembly in the chipping hammer. A spring that has taken a set gives soft or sticky action long before it actually breaks.

It appears on the CP 0012 Chipping Hammer and CP 0016 Chipping Hammer, and on 3 other machines breakdown. Pull up the diagram and confirm the reference number for your serial before ordering.

If you need the parts around it, the parts diagram library has the full breakdown library, and the Chicago Pneumatic tool range covers the machines themselves. Stocked in Denver orders placed by 4 PM ET ship the same day when the part is on the shelf.

• Part number: H3437857
• Also listed as: 3310190012
• Manufacturer: Chicago Pneumatic
• Crowder SKU: CP-H3437857
• Listed on breakdowns for: CP 0012 Chipping Hammer, CP 0016 Chipping Hammer, CP 4131 Chipping Hammer, CP 4132 4133 4134 4136 Chipping Hammer, TEX319 320 321 419 421 Chipping Hammer